Heretofore, a relay terminal block 200 for a power supply is known which has a plug-in connector (male) 220 connected to a feeding cable 210, and a plug-in connector (female) 240 connected to the other feeding cable 230 and in which the plug-in connectors 220 and 240 are fitted to each other to thereby connect the feeding cables 210 and 230, as shown in FIG. 14 (see, for example, Patent Document 1).
The plug-in connector (male) 220 is mounted to a plug-in module (not shown) while the plug-in connector (female) 240 is mounted to a receiving structure (not shown) for receiving the plug-in module (not shown).